Impact of food allergy on the growth of children with moderate-severe atopic dermatitis

Insights into the clinical, immunologic, and genetic underpinnings of food allergy

The last few decades have seen striking changes in the field of food allergy. The prevalence of the disease has risen dramatically in many parts of the globe, and management of the condition has undergone major revision. While delayed introduction of common allergenic foods during infancy was advised for many years, the learning early about peanut allergy (LEAP) trial and other studies led to a major shift in infant feeding practices, with deliberate early introduction of these foods now recommended. Additionally, the Food and Drug Administration approved the first treatment for food allergy in 2020-a peanut oral immunotherapy (OIT) product that likely represents just the beginning of new immunotherapy-based and other treatments for food allergy. Our knowledge of the environmental and genetic factors contributing to the pathogenesis of food allergy has also undergone transformational advances. Here, we will discuss our efforts to improve the clinical care of patients with food allergy and our understanding of the immunological mechanisms contributing to this common disease.

The contribution of milk substitutes to the nutritional status of children with cow's milk allergy

BACKGROUND

The impact of alternative milk substitutes on the nutritional status of children with cow's milk allergy (CMA), the prevailing cause of food allergies, is unresolved.

METHODS

A cross-sectional study was performed in children older than 2 years with IgE-mediated CMA. Patients' clinical characteristics, anthropometric measurements, dietary intake (by 3-day food diary), and biochemical markers of nutritional status were assessed.

RESULTS

One hundred two children with CMA (68.6% boys; median age, 3.7 years; 51% multiple food allergies) were evaluated. 44.1% of the children consumed plant-based beverages (PBB), 19.6% therapeutic formula and 36.3% did not consume any milk substitutes. In all age groups, dietary calcium, riboflavin, and vitamin D intake of those who did not use milk substitutes were lower than those who consumed formula or PBB (p < .01). Also in the 2-3 years old age group, dietary zinc (p = .011) and iron intake (p = .004) of the formula-fed group was higher. Formula-fed patients had higher levels of 25-OH vitamin D (μg/L) and serum vitamin B12 (ng/L) than PBB-fed patients (respectively; p < .001, p = .005) and those who did not consume any milk substitute (p < .001). Patients of all ages who did not utilize a milk substitute failed to obtain an adequate amount of dietary calcium.

CONCLUSION

The use of milk substitutes positively affects dietary calcium, riboflavin, and vitamin D intake in CMA, but their contribution is variable. Those who do not use milk substitutes are at greater risk inadequate of dietary calcium intake. Personalized nutritional advice, given the clinical diversity and the impact of individual differences, is required.

Relationship between growth and food avoidance with food allergy at age 3 years: The Japan Environment and Children's Study (JECS)

Background

Basic management for food allergy (FA) is eliminating causative food from the diet, which can impact normal growth. This study examined the association between food avoidance and growth failure among children with FA aged 0-3 years using the Japan Environment and Children's Study (JECS) data.

Methods

Data on height, weight, and FA history registered were collected using self-administered questionnaires at age 1, 1.5, 2, and 3 years. A general linear model was used to examine whether dietary restriction affected body size. Height, weight, and body mass index (BMI) were adjusted for age in months using standard deviation (SD) scores for each age group by month of measurement. Presence of FA or dietary restriction was used as a binary variable.

Results

Of the 38 477 participants included in this analysis, 4070 with FAs had significantly lower SD scores for height and weight at age 3 years. With milk avoidance, significantly lower SD scores for height (male: β = -0.097 [95%CI: 0.175, -0.019], female: β = -0.103 [95%CI: 0.204, -0.002]), a significantly lower SD score for weight (male: β = -0.115[95%CI: 0.187, -0.043], female β = -0.114[95%CI: 0.203, -0.026]) were observed. Soy avoidance in males marked a lower SD score for height (β = -0.307 [95%CI: 0.474, -0.140]). Continued food avoidance until age 3 resulted in significantly lower SD score for height and weight regardless of gender.

Conclusion

Growth impairment was observed with food avoidance at age 3 years. Growth impairment were more obvious in males than in females. With regards food items, the impact of milk and soy was more significant.

Longitudinal assessment of early growth in children with IgE- and non-IgE-mediated food allergy in a healthy infant cohort

BACKGROUND

There are conflicting associations reported between food allergies (FAs) and poor growth, with some indication that children with multiple FAs are at highest risk.

OBJECTIVE

We analyzed longitudinal weight-for-length (WFL) trajectories from our healthy cohort to evaluate growth in children with IgE-mediated FAs and food protein-induced allergic proctocolitis (FPIAP), a non-IgE-mediated FA.

METHODS

Our observational cohort of 903 healthy newborn infants was prospectively enrolled to evaluate the development of FAs. Longitudinal mixed effects modeling was used to compare differences in WFL among children with IgE-FA and FPIAP, compared with unaffected children, through age 2.

RESULTS

Among the 804 participants who met inclusion criteria, FPIAP cases had significantly lower WFL than unaffected controls during active disease, which resolved by 1 year of age. In contrast, children with IgE-FA had significantly lower WFL than unaffected controls after 1 year. We also found that children with IgE-FA to cow's milk had significantly lower WFL over the first 2 years of age. Children with multiple IgE-FAs had markedly lower WFL over the first 2 years of age.

CONCLUSION

Children with FPIAP have impaired growth during active disease in the first year of age which resolves, whereas children with IgE-FA, particularly those with multiple IgE-FA, have impaired growth more prominently after the first year of age. It may be appropriate to focus nutritional assessment and interventions accordingly during these higher risk periods in these patient populations.

Clinical study on prevention of atopic dermatitis by oral administration of probiotics in infants

INTRODUCTION

This study aimed to investigate the preventive effects of oral administration of probiotics on the incidence and severity of atopic dermatitis (AD) in infants.

MATERIAL AND METHODS

A total of 396 full-term infants were enrolled in this study. Of these, 132 newborns without a family history of AD were assigned to group A, and the other 264 newborns were randomly divided into groups B and C. Infants in groups A and B were solely breastfed, while probiotics were administered to those in group C as well as breastfeeding. The information of all subjects was recorded, and the incidence of AD was followed up. The levels of serum IgE and IL-4 were measured at the age of 3 years.

RESULTS

The incidence of AD in infants in group B was higher than that in group A at 3 months, 4-6 months, and 7-36 months after birth, together with increased symptom scores. For infants in group C, the incidence of AD at 4-6 months and 7-36 months after birth and the SCORAD scores at 0-3 months and 4-6 months after birth were lower than those in group B. The levels of IgE and IL-4 in group B were higher than those in groups A and C at 36 months old.

CONCLUSIONS

Adding probiotics could favor the establishment of the intestinal microecological balance in the neonatal period, thereby reducing the incidence of AD, decreasing the levels of serum immune indexes and alleviating the severity of the disease.

Dietary Elimination for the Treatment of Atopic Dermatitis: A Systematic Review and Meta-Analysis

BACKGROUND

The influence of diet on atopic dermatitis (AD) is complex, and the use of dietary elimination as a treatment has conflicting views.

OBJECTIVE

To systematically review the benefits and harms of dietary elimination for the treatment of AD.

METHODS

We searched MEDLINE, Embase, AMED, PsycINFO, and the Cochrane Central Register of Controlled Trials from inception to January 18, 2022, without language restrictions, for randomized controlled trials (RCTs) and observational studies comparing dietary elimination and no dietary elimination for the treatment of AD. We conducted random-effects meta-analyses of eczema outcomes. We used the grading of recommendations, assessment, development, and evaluation approach to assess certainty of evidence (CRD42021237953).

RESULTS

Ten RCT (n = 599; baseline median of study mean age, 1.5 years; median of study mean SCOring Atopic Dermatitis index, 20.7, range, 3.5-37.6) were included in the meta-analysis. Compared with no dietary elimination, low-certainty evidence showed that dietary elimination may slightly improve eczema severity (50% with vs 41% without dietary elimination improved the SCOring Atopic Dermatitis index by a minimally important difference of 8.7 points, risk difference of 9% [95% CI, 0-17]), pruritus (daytime itch score [range, 0-3] mean difference, -0.21 [95% CI, -0.57 to 0.15]), and sleeplessness (sleeplessness score [range, 0-3] mean difference, -0.47 [95% CI, -0.80 to -0.13]). There were no credible subgroup differences based on elimination strategy (empiric vs guided by testing) or food-specific sensitization. Insufficient data addressed harms of elimination diets among included RCTs, although indirect evidence suggests that elimination diets may increase the risk for developing IgE-mediated food allergy.

CONCLUSIONS

Dietary elimination may lead to a slight, potentially unimportant improvement in eczema severity, pruritus, and sleeplessness in patients with mild to moderate AD. This must be balanced against potential risks for indiscriminate elimination diets including developing IgE-mediated food allergy and withholding more effective treatment options for AD.

Failure to Thrive in the Outpatient Clinic: A New Insight

Failure to thrive (FTT) is an abnormal growth pattern determined by inadequate nutrition. It is a common problem in children, representing 5% to 10% of patients seen in an outpatient setting. Many definitions have been proposed based on anthropometric deterioration; however, they show poor concordance. No single definition is sufficiently sensitive in identifying faltering growth whilst a combination of multiple criteria seems more accurate. In light of the recent redefinition of pediatric malnutrition as a disequilibrium between requirements and intakes of energy, and macro- and micronutrients, a wider conception of FTT as an unsatisfactory nutritional status related to poor growth and health is useful. Although the most severe problems of micronutrient malnutrition are found in developing countries, people of all regions of the world can be affected by micronutrient deficiencies (MNDs), a form of undernutrition with relevant effects on growth and health. Changes in diets and lifestyle, elimination diets, food insecurity, and food intake disorders create the conditions at risk of faltering growth and MNDs. This new insight integrates the "classical" anthropometric criteria for definition and treatment, in the aim of warranting both a regular increase in size and an overall adequate development and health status.

Are avoidance diets still warranted in children with atopic dermatitis?

Nearly 40% of children with moderate-to-severe atopic dermatitis (AD) have IgE-mediated food allergy (FA). This clinical observation has been extensively documented by experimental data linking skin inflammation in AD to FA, as well as by food challenges reproducing symptoms and avoidance diets improving AD. Although food avoidance may improve AD, avoidance diets do not cure AD, may even have detrimental effects such as progression to immediate-type allergy including anaphylactic reactions, and may significantly reduce the quality of life of the patient and the family. AD care should focus upon optimal medical management, rather than dietary elimination. Food allergy testing is primarily indicated when immediate-type allergic reactions are a concern. In recalcitrant AD, if food is being considered a possible chronic trigger, a limited panel of foods may be tested. An avoidance diet is only indicated in patients clearly identified as food allergic by an appropriate diagnostic food challenge, and after adequately informing the family of the limited benefits, and possible harms of an elimination diet.

The clinical and mechanistic intersection of primary atopic disorders and inborn errors of growth and metabolism

Dynamic changes in metabolism have long been understood as critical for both the initiation and maintenance of innate and adaptive immune responses. A number of recent advances have clarified details of how metabolic pathways can specifically affect cellular function in immune cells. Critical to this understanding is ongoing study of the congenital disorders of glycosylation and other genetic disorders of metabolism that lead to altered immune function in humans. While there are a number of immune phenotypes associated with metabolic derangements caused by single gene disorders, several genetic mutations have begun to link discrete alterations in metabolism and growth specifically with allergic disease. This subset of primary atopic disorders is of particular interest as they illuminate how hypomorphic mutations which allow for some residual function of mutated protein products permit the "abnormal" allergic response. This review will highlight how mutations altering sugar metabolism and mTOR activation place similar constraints on T lymphocyte metabolism to engender atopy, and how alterations in JAK/STAT signaling can impair growth and cellular metabolism while concomitantly promoting allergic diseases and reactions in humans.

Growth Pattern, Resting Energy Expenditure, and Nutrient Intake of Children with Food Allergies

Growth impairment has been reported in children with food allergies (FA). However, the available data on the dietary intake of FA children are controversial, and no data are available on their resting energy expenditure (REE). The aim of this study was to test whether REE differs between FA and healthy children. In this study, 30 FA children were matched by sex and age, with 31 healthy controls using coarsened exact matching (CEM). Their REE was measured by indirect calorimetry (IC). Energy and macronutrient intake were evaluated using a three-day dietary record. Between-group comparisons were performed by robust median regression using CEM-related weights. The association of REE with allergies was also evaluated using robust median regression models. Anthropometric measurements, REE, and nutrient intake were similar in FA children and matched controls. Taking into account the association of REE with gender and age, a statistically significant but biologically negligible association was detected between median REE and allergy status (+9% in FA children). In conclusion, we did not find any biologically relevant difference in REE, anthropometry, and dietary intake in children with FA compared to healthy children.

Growth of children with food allergies in Singapore

Background

Although it is known that children with food allergies are at risk of impaired growth, this has not been well studied in South-East Asia.

Objective

The aim of this cross-sectional study is to survey the growth of children with food allergies in Singapore and the factors impacting it.

Methods

Anthropometric data, demographic data, type of food allergy, foods eliminated, and atopic comorbidities were recorded. Malnutrition was defined using World Health Organization standards (≤-2 z-score for weight-for-height [WH], weight-for-age [WA], and height-for-age [HA]).

Results

Seventy-four patients (51% male) were recruited over 1 month, with median age at diagnosis of 8 months (interquartile range [IQR], 4–13 months) and at data collection of 25 months (IQR, 14–48 months). Sixty-two (84%) had IgE-mediated allergy, 8 (11%) mixed IgE and non-IgE, and 4 (5%) non-IgE-mediated allergy. Food exclusions: 55% one food, 27% two foods, 8% three to four foods, and 10% ≥5 foods. Only 1% were underweight (WA ≤ -2 z-score) and 3% had WA ≥ +2 z-score. Having a mixed type food allergy significantly reduced WA (p = 0.023). WA was significantly lower for those referred to the dietitian (p = 0.027). 5.4% were stunted (HA ≤ -2 z-score). Factors significantly associated with stunting were underlying eczema (p = 0.03) and having an IgE-mediated (p = 0.03) or mixed type food allergy (p = 0.002). One point four percent (1.4%) were undernourished (WH ≤ -2 z-score) and 1.4% were overweight (WH ≥ +2 z-score). Multivariate regression analysis found that children with mixed type food allergies were significantly shorter (z-score -1 lower). Children had a lower WA if they had skin involvement as part of their symptom presentation.

Conclusion

This is the first survey documenting growth in children with food allergy in Singapore. Eczema, IgE-mediated and mixed type allergies are associated with poorer growth rates in these children. Early, individualised nutritional intervention is recommended for all children with food allergy.

Nutritional disorders resulting from food allergy in children

The elimination of food allergens that contribute essential nutrients in paediatrics may lead to the development of nutritional disorders. The most common nutritional disorders include poor growth, micronutrient deficiencies and feeding difficulties. Of the aforementioned, growth faltering has been well studied and is seen as a common presenting factor in paediatric food allergy. However, the use of different criteria and cut-off values makes it difficult to establish the overall effect. The impact of number and type of foods eliminated and comorbidities has yielded varying results, although there seems to be a trend towards worsening growth with atopic dermatitis and the avoidance of cow's milk. Low micronutrient intake is common in paediatric food allergy; however, a low intake does not necessarily translate into a deficiency as measured by biomarkers. Vitamin D and calcium have been well studied, and a long-lasting impact on bone mineral density has been found. However, other micronutrient deficiencies have also been found and should also be considered. Feeding difficulties is a common complaint in clinical practice, but limited data have been published in food allergy. Poor growth and reflux/vomiting have been shown to be associated with feeding difficulties, in particular in non-IgE-mediated food allergies. There seems to be a long-lasting effect on feeding, in particular in cow's milk allergy, which needs to be taken into account with dietary input. The interplay between growth, feeding difficulties and micronutrient deficiencies has been implied in some studies, but cause and effect is not well established and requires further research.